The other 22 players on your roster can be salaried any way possible. This basically ensures team/roster parity and realism.

Also everyone must draft:

*5'500 plate appearances
*1'450 innings pitched

To be clear though you do not HAVE to have palyers between 200k-499k, 500k-999k, milto 1.5mil, YOU JUST CAN ONLY HAVE 1 INSTANCE OF EACH WHEN CREATING YOUR ROSTER. If your 25th man has a salary of 1.5mil on the dot that's cool.